Lamp and method of manufacturing same

ABSTRACT

A lamp including a plurality of light emitting devices and heat sinks can be configured to dissipate heat generated by the plurality of light emitting devices. The heat sinks can be branched into a generally Y-shaped configuration as viewed in a section that includes a primary optical axis of the vehicle lamp. One of the light emitting devices is connected to one of the branched parts of the heat sinks. Another light emitting device is connected to the other branched part of the heat sinks.

This application claims the priority benefit under 35 U.S.C. § 119 ofJapanese Patent Application No. 2007-326773 filed on Dec. 19, 2007,which is hereby incorporated in its entirety by reference.

BACKGROUND

1. Technical Field

The presently disclosed subject matter relates to a lamp which has aplurality of light emitting devices and a heat sink configured todissipate heat generated by the plurality of light emitting devices, anda method for manufacturing the same. In particular, the presentlydisclosed subject matter relates to a vehicle lamp which can dissipateheat generated by a plurality of light emitting devices by means of aheat sink, and a method for manufacturing the same.

2. Description of the Related Art

Conventionally, there have been known lamps that have a plurality oflight emitting devices and a heat sink configured to dissipate heatgenerated by the plurality of light emitting devices. Among the examplesof vehicle lamps of this type, one of interest is shown in FIG. 1 ofJapanese Patent Application Laid-Open No. 2006-134810 (hereinafter,referred to as a conventional vehicle lamp).

The conventional vehicle lamp has a plurality of light emitting devices(for example, a main LED and a sub LED), and a heat sink (being aradiator plate) configured to dissipate heat generated by these devices.More specifically, a first light emitting device (the main LED) is fixedto the top of the heat sink (the radiator plate), and a second lightemitting device is fixed to the bottom of the heat sink. That is, theheat sink is shared between the first light emitting device and thesecond light emitting device.

The heat sink of the conventional vehicle lamp is formed in a generallyI-shaped configuration when seen in a vertical section that includes theprimary optical axis of the vehicle lamp. As mentioned above, the firstlight emitting device is fixed to the top of the heat sink, and thesecond light emitting device is fixed to the bottom of the heat sink.

In the conventional vehicle lamp, the heat sink therefore has arelatively small surface area per single light emitting device (the mainLED or the sub LED). This makes it difficult or sometimes impossible forthe conventional vehicle lamp to sufficiently dissipate the heatgenerated by the plurality of light emitting devices (the main LED andthe sub LED) through the heat sink.

SUMMARY

The presently disclosed subject matter was devised in view of these andother features, problems, characteristics, and in association with theconventional art. According to an aspect of the presently disclosedsubject matter, a lamp can be provided which is configured tosufficiently dissipate heat generated by a plurality of light emittingdevices by means of a heat sink.

According to another aspect of the presently disclosed subject matter, alamp can include: a plurality of light emitting devices including atleast first and second light emitting devices; and a first heat sinkconfigured to dissipate heat generated by the plurality of lightemitting devices, the first heat sink having a first branched part and asecond branched part in a generally Y-shaped configuration in across-section including a primary optical axis of the lamp, the firstbranched part being connected with at least the first light emittingdevice, the second branched part being connected with at least thesecond light emitting device.

According to still another aspect of the presently disclosed subjectmatter, the above lamp can further include: a first reflector configuredto reflect light emitted from the first light emitting device toward thefront with respect to the primary optical axis of the lamp, the firstreflector having a first reflecting surface configured to reflect a beamof light that is emitted from the first light emitting device behind aprimary optical axis of the first light emitting device with respect tothe primary optical axis of the lamp, and a second reflecting surfaceconfigured to reflect a beam of light that is emitted from the firstlight emitting device in a frontward direction of the primary opticalaxis of the first light emitting device with respect to the primaryoptical axis of the lamp; and a second reflector configured to reflectlight emitted from the second light emitting device toward the frontwith respect to the primary optical axis of the lamp, the secondreflector having a third reflecting surface configured to reflect a beamof light that is emitted from the second light emitting device behind aprimary optical axis of the second light emitting device with respect tothe primary optical axis of the lamp, and a fourth reflecting surfaceconfigured to reflect a beam of light that is emitted from the secondlight emitting device in a frontward direction of the primary opticalaxis of the second light emitting device with respect to the primaryoptical axis of the lamp. In this lamp, the light beam reflected fromthe first reflecting surface and the light beam reflected from the thirdreflecting surface can be projected forward with respect to the primaryoptical axis of the lamp at relatively small angles to the primaryoptical axis of the lamp, and the light beam reflected from the secondreflecting surface and the light beam reflected from the fourthreflecting surface can be projected forward with respect to the primaryoptical axis of the lamp at relatively large angles to the primaryoptical axis of the lamp.

According to still another aspect of the presently disclosed subjectmatter, the above lamp can further include an outer lens. In this lamp,the light beam reflected from the second reflecting surface and thelight beam reflected from the fourth reflecting surface can cross eachother near the primary optical axis of the lamp, and the outer lens canhave a lens cut area near the position where the light beam that isreflected from the second reflecting surface and the light beam that isreflected from the fourth reflecting surface cross each other.

According to still another aspect of the presently disclosed subjectmatter, the above lamp can be configured such that the lens cut area canbe arranged in front of the first and second branched parts of the firstheat sink, and outlines of the first and second branched parts and anoutline of the lens cut area can be generally consistent with each otherwhen seen from the front with respect to the primary optical axis of thelamp.

According to still another aspect of the presently disclosed subjectmatter, the above lamp can be configured such that a circuit substrateconfigured to supply power to the plurality of light emitting devicescan be connected with first and second sides of an unbranched part ofthe first heat sink, an end of the unbranched part opposite from thefirst and second branched parts can be thermally connected with ahousing of the lamp, and a border area between the first and secondbranched parts and the unbranched part can be thermally connected withthe housing of the lamp.

According to still another aspect of the presently disclosed subjectmatter, the above lamp can be configured such that the circuit substrateconfigured to supply power to the plurality of light emitting devicescan be made of a flexible substrate, a half of the flexible substratecan be connected with the first side of the unbranched part of the firstheat sink, and the other half of the flexible substrate can be connectedwith the second side of the unbranched part of the first heat sink.

According to still another aspect of the presently disclosed subjectmatter, the above lamp can be manufactured by a method including:joining a second heat sink to a half of the flexible substrate inadvance before the half of the flexible substrate is connected with thefirst side of the unbranched part of the first heat sink; joining athird heat sink to the other half of the flexible substrate in advancebefore the other half of the flexible substrate is connected with thesecond side of the unbranched part of the first heat sink; joining thesecond heat sink to the first side of the unbranched part of the firstheat sink, thereby connecting the half of the flexible substrate withthe first side of the unbranched part of the first heat sink; andjoining the third heat sink to the second side of the unbranched part ofthe first heat sink, thereby connecting the other half of the flexiblesubstrate with the second side of the unbranched part of the first heatsink.

According to still another aspect of the presently disclosed subjectmatter, the above lamp can be used as a vehicle lamp including aheadlamp, turn signal lamp, position lamp, daytime running lamp, highbeam lamp, fog lamp, tail lamp, stop lamp, traffic lamp, and the like.Of course, the lamp could also be used as a general purpose lamp,possibly for housing applications.

A vehicle lamp according to one of the aspects of the presentlydisclosed subject matter can have a plurality of light emitting devicesincluding at least first and second light emitting devices, and a firstheat sink configured to dissipate heat generated by the plurality oflight emitting devices. In addition, the first heat sink can include afirst branched part and second branched part in a generally Y-shapedconfiguration in a section including the primary optical axis of thevehicle lamp. The first branched part can be connected with at least thefirst light emitting device, and the second branched part can beconnected with at least the second light emitting device.

Consequently, the heat generated by the first light emitting device canbe dissipated by the first branched part of the first heat sink, notonly from the side where the light emitting device is connected but alsofrom the side where it is not connected.

The heat generated by the second light emitting device can be dissipatedby the second branched part of the first heat sink, not only from theside where the light emitting device is connected but also from the sidewhere it is not connected.

According to the vehicle lamp of the above aspect, it is thereforepossible to improve the efficiency of heat dissipation with respect tothe heat generated by the plurality of light emitting devices whencompared with the conventional vehicle lamp (shown in FIG. 1 of JapanesePatent Application Laid-Open No. 2006-134810) where the heat sink isformed in a generally I-shaped configuration when seen in the verticalplane including the primary optical axis of the vehicle lamp. That is,the heat generated by the plurality of light emitting devices can besufficiently dissipated by the first heat sink.

The vehicle lamp of the foregoing configuration can prevent a shortenedlife, dropped luminous intensity, and discolored light of the lightemitting devices, which might result from insufficient dissipation ofthe heat generated by the plurality of light emitting devices.

In the vehicle lamp of the foregoing configuration, the first heat sinkcan be branched into the generally Y-shaped configuration in ahorizontal section that includes the primary optical axis of the vehiclelamp. The presently disclosed subject matter is not limited thereto,however. Instead, the first heat sink may be branched so as to have agenerally Y-shaped configuration in a vertical section that includes theprimary optical axis of the vehicle lamp, or in an arbitrary crosssection including the primary optical axis of the vehicle lamp otherthan the horizontal section or the vertical section.

In the vehicle lamp of the foregoing configuration, the first heat sinkhaving the generally Y-shaped section can be formed by joining twogenerally L-shaped members. The presently disclosed subject matter isnot limited thereto, however. Instead, the first heat sink of generallyY-shape configuration may be made of a single member that is so formedby molding, such as aluminum die-casting.

A vehicle lamp according to another aspect of the presently disclosedsubject matter can have the first reflector configured to reflect thelight emitted from the first light emitting device toward the front withrespect to the primary optical axis of the vehicle lamp, and the secondreflector configured to reflect the light emitted from the second lightemitting device toward the front with respect to the primary opticalaxis of the vehicle lamp. The first (or second) reflector can have thefirst reflecting surface (or third reflecting surface) configured toreflect the beam of light that is emitted from the light emitting devicebehind the primary optical axis of the light emitting device withrespect to the direction of the vehicle lamp. The first reflector (orsecond reflector) can also have the second reflecting surface (or fourthreflecting surface) configured to reflect the beam of light that isemitted from the light emitting device in a frontward direction of theprimary optical axis of the light emitting device with respect to thedirection of the vehicle lamp.

In the vehicle lamp of the foregoing configuration, the light beamreflected from the first reflecting surface and the light beam reflectedfrom the third reflecting surface can be projected forward with respectto the primary optical axis of the vehicle lamp at relatively smallangles to the primary optical axis of the vehicle lamp. The light beamreflected from the second reflecting surface and the light beamreflected from the fourth reflecting surface can be projected forwardwith respect to the primary optical axis of the vehicle lamp atrelatively large angles to the primary optical axis of the vehicle lamp.

In other words, the beam of light that is emitted from the first lightemitting device in a frontward direction of the primary optical axis ofthis light emitting device with respect to the direction of the vehiclelamp is not reflected from the first reflector so as to be projected infront of the vehicle lamp at relatively small angles to the primaryoptical axis of the vehicle lamp, but can be reflected from the firstreflector so as to be projected in front of the vehicle lamp atrelatively large angles to the primary optical axis of the vehicle lamp.This allows miniaturization of the first reflector.

Furthermore, in the vehicle lamp of the foregoing configuration, thebeam of light that is emitted from the second light emitting device in afrontward direction of the primary optical axis of this light emittingdevice with respect to the direction of the vehicle lamp is notreflected from the second reflector so as to be projected in front ofthe vehicle lamp at relatively small angles to the primary optical axisof the vehicle lamp, but can be reflected from the second reflector soas to be projected in front of the vehicle lamp at relatively largeangles to the primary optical axis of the vehicle lamp. This allowsminiaturization of the second reflector.

In a vehicle lamp according to another aspect of the presently disclosedsubject matter, the light beam reflected from the second reflectingsurface and the light beam reflected from the fourth reflecting surfacecan cross each other near the primary optical axis of the vehicle lamp.In addition, the outer lens can have a lens cut area near the positionwhere the light beam reflected from the second reflecting surface andthe light beam reflected from the fourth reflecting surface cross eachother. It follows that the lens cut area formed on the outer lens of thevehicle lamp can diffuse the light beam reflected from the secondreflecting surface. The lens cut area can also diffuse the light beamreflected from the fourth reflecting surface.

This allows the miniaturization of the outer lens of the vehicle lamp,and by extension the miniaturization of the entire vehicle lamp, whencompared with the case where lens cut areas for the respectivereflecting surfaces are provided separately from the outer lens of thevehicle lamp.

In a vehicle lamp according to another aspect of the presently disclosedsubject matter, the lens cut area can be arranged in front of the firstand second branched parts of the first heat sink. The outlines of thefirst and second branched parts and the outline of the lens cut area canbe generally consistent with each other when seen from the front of thevehicle lamp. The lens cut area can thus prevent the first and secondbranched parts of the first heat sink from being visible from the frontof the vehicle lamp. In other words, the lens cut area for diffusing thelight beam reflected from the second reflecting surface and the lightbeam reflected from the fourth reflecting surface can be used as meansfor preventing the first and second branched parts of the first heatsink from being visible from the front of the vehicle lamp.

This can suppress the cost of the entire vehicle lamp when compared withthe case where a shielding part is provided aside from the lens cutarea.

In a vehicle lamp according to another aspect of the presently disclosedsubject matter, the circuit substrate configured to supply power to theplurality of light emitting devices can be connected with both sides ofthe unbranched part of the first heat sink. The end of the unbranchedpart opposite from the first and second branched parts can be thermallyconnected with the housing of the vehicle lamp. The border area betweenthe branched parts and the unbranched part can also be thermallyconnected with the housing of the vehicle lamp. According to thisconfiguration, some of the heat that is generated by components on thecircuit substrate in connection with both sides of the unbranched partof the first heat sink can be transferred to the housing of the vehiclelamp through the end of the unbranched part, and can be dissipated fromthe housing of the vehicle lamp. Some of the heat generated by thecomponents on the circuit substrate can also be transferred to thehousing of the vehicle lamp through the border area between the branchedand unbranched parts, and can be dissipated from the housing of thevehicle lamp.

In other words, in the vehicle lamp of the foregoing configuration, theheat generated by the components on the circuit substrate in connectionwith the unbranched part of the heat sink can be prevented from transferto the area of the first heat sink where the plurality of light emittingdevices are connected. This can suppress a drop in the efficiency ofheat dissipation for the plurality of light emitting devices, whichmight result if the heat generated by the components on the circuitsubstrate is transferred to the area of the first heat sink where theplurality of light emitting devices are connected.

Put another way, heat dissipation channels can be provided for the heatgenerated by the components on the circuit substrate so that the heatgenerated by the components on the circuit substrate configured tosupply power to the plurality of light emitting devices can bedissipated without reaching the plurality of light emitting devices.This can improve the efficiency of heat dissipation for the plurality oflight emitting devices as compared to the case without sufficient heatdissipation channels.

In a vehicle lamp according to another aspect of the presently disclosedsubject matter, the circuit substrate configured to supply power to theplurality of light emitting devices can be made of a flexible substrate.A half of the flexible substrate can be connected with the first side ofthe unbranched part of the first heat sink. The other half of theflexible substrate can be connected with the second side of theunbranched part of the first heat sink. This can reduce the parts countof the entire vehicle lamp, and by extension the assembly cost of theentire vehicle lamp, when compared with the case where rigid substratesare connected to the respective sides of the first heat sink. Morespecifically, it is possible to reduce the number of substrates, as wellas wiring, couplers, and the like for connecting one rigid substrate tothe other rigid substrate. The entire vehicle lamp can thus be reducedin size.

The vehicle lamp of the foregoing configuration allows an improvedpacking density for the components on the circuit substrate. Morespecifically, a thin flexible substrate with low thermal resistance canbe used to transfer the heat generated by the components on thesubstrate to the first heat sink quickly. This can reduce the thermalload on the components, so that a plurality of components can be mountedon the substrate with an increased package density.

According to a method of manufacturing a vehicle lamp according toanother aspect of the presently disclosed subject matter, the secondheat sink can be joined to a half of the flexible substrate in advancebefore the half of the flexible substrate is connected with the firstside of the unbranched part of the first heat sink. The third heat sinkcan be joined to the other half of the flexible substrate in advancebefore the other half of the flexible substrate is connected with thesecond side of the unbranched part of the first heat sink. Then, thesecond heat sink can be joined to the first side of the unbranched partof the first heat sink, whereby the half of the flexible substrate canbe connected with the first side. The third heat sink can be joined tothe second side of the unbranched part of the first heat sink, wherebythe other half of the flexible substrate can be connected with thesecond side. This allows improved workability when assembling theflexible substrate and the first heat sink, as compared to the casewhere the halves of the flexible substrate are directly joined to therespective sides.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other characteristics, features, and advantages of thepresently disclosed subject matter will become clear from the followingdescription with reference to the accompanying drawings, wherein:

FIGS. 1A and 1B are diagrams showing a vehicle lamp according to a firstexemplary embodiment made in accordance with principles of the presentlydisclosed subject matter;

FIGS. 2A to 2C are diagrams showing different views of the vehicle lampof FIGS. 1A and 1B;

FIGS. 3A and 3B are diagrams showing light beams projected from thevehicle lamp of FIGS. 1A and 1B; and

FIGS. 4A to 4B are diagrams showing light beams projected from thevehicle lamp of FIGS. 1A and 1B.

DETAILED DESCRIPTION OF EMBODIMENTS

A description will now be made below to exemplary embodiments of vehiclelamps of the presently disclosed subject matter with reference to theaccompanying drawings.

Hereinafter, an embodiment of the vehicle lamp according to thepresently disclosed subject matter will be described. FIGS. 1A, 1B, 2A,2B, and 2C are diagrams showing the vehicle lamp according to thepresent exemplary embodiment. To be more specific, FIG. 1A is asectional view of the vehicle lamp according to the present exemplaryembodiment, taken along a horizontal plane that includes a primaryoptical axis CL of the vehicle lamp along which light is emitted fromthe lamp in an optical axis light emitting direction. FIG. 1B is a frontview of the vehicle lamp according to the present exemplary embodiment.FIG. 2A is a sectional view taken along line A-A of FIG. 1B. FIG. 2B isa sectional view of the vehicle lamp according to the present exemplaryembodiment, taken along a vertical plane that includes the primaryoptical axis CL of the vehicle lamp. FIG. 2C is a developed view of anassembly that constitutes a part of the vehicle lamp according to thepresent exemplary embodiment, the assembly including heat sinks 4 a and4 b and a flexible substrate 5.

FIGS. 3A, 3B, 4A, and 4B are diagrams showing beams of light emittedfrom the vehicle lamp of FIGS. 1A and B. More specifically, FIG. 3A is adiagram showing light beams L1 and L2 that are emitted from a lightemitting device 1 a in a direction rearward (above in the diagram) withrespect to a primary optical axis CL1 a of the light emitting device 1a. In other words, light beams L1 and L2 have directional vectorcomponents in both the direction opposite the optical axis lightemitting direction and a direction perpendicular to the optical axislight emitting direction. The light beams L1 and L2 are reflected at areflecting surface 7 a 1 of a reflector part 7 a of a reflector 7, andprojected in the illuminating direction of the vehicle lamp (downward inthe diagram). FIG. 3B is a diagram showing light beams L3, L4, and L5that are emitted from the light emitting device 1 a in a forwarddirection (below, in the diagram) with respect to the primary opticalaxis CL1 a of the light emitting device 1 a. In other words, light beamsL3, L4, and L5 have directional vector components in both the directionalong the optical axis light emitting direction and a directionperpendicular to the optical axis light emitting direction. The lightbeams L3, L4, and L5 are reflected at a reflecting surface 7 a 2 of thereflector part 7 a of the reflector 7 and projected in the illuminatingdirection and having a vector component in the optical axis lightemitting direction of the vehicle lamp (such the light is directed tothe lower right, in the diagram).

FIG. 4A is a diagram showing light beams L6 and L7 that are emitted froma light emitting device 1 b in a rearward direction (above, in thediagram) with respect to a primary optical axis CL1 b of the lightemitting device 1 b. In other words, light beams L6 and L7 havedirectional vector components in both the direction opposite the opticalaxis light emitting direction and a direction perpendicular to theoptical axis light emitting direction. The light beams L6 and L7 arereflected at a reflecting surface 7 b 1 of a reflector part 7 b of thereflector 7, and projected in the illuminating direction of the vehiclelamp (downward, in the diagram). FIG. 4B is a diagram showing lightbeams L8, L9, and L10 that are emitted from the light emitting device 1b in a forward direction (below, in the diagram) with respect to theprimary optical axis CL1 b of the light emitting device 1 b. In otherwords, light beams L8, L9, and L10 have directional vector components inboth the direction of the optical axis light emitting direction and adirection perpendicular to the optical axis light emitting direction.The light beams L8, L9, and L10 are reflected at a reflecting surface 7b 2 of the reflector part 7 b of the reflector 7, and projected in theilluminating direction and having a vector component in the optical axislight emitting direction of the vehicle lamp (such that the light isdirected to the lower left, in the diagram).

In the vehicle lamp of the present exemplary embodiment, as shown inFIG. 1A, the light emitting device 1 a, such as an LED, can be mountedon a base member 2 a having a high thermal conductivity. The lightemitting device 1 b such as an LED can be mounted on a base member 2 bhaving a high thermal conductivity. The base member 2 a can be screwedor otherwise joined to a front part 3 a 1 (lower part, in the diagram)of a generally L-shaped heat sink 3 a which can be made of a high heatconductive material such as aluminum. The base member 2 b can be screwedor otherwise joined to a front part 3 b 1 (lower part, in the diagram)of a generally L-shaped heat sink 3 b which can be made of a high heatconductive material such as aluminum.

In the vehicle lamp of the present exemplary embodiment, as shown inFIG. 1A, the base members 2 a and 2 b can be interposed between thelight emitting devices 1 a and 1 b and the front parts 3 a 1 and 3 b 1of the heat sinks 3 a and 3 b, respectively. The presently disclosedsubject matter is not limited thereto, however. Instead, the lightemitting devices and the front parts of the respective heat sinks may bedirectly connected to each other.

In the vehicle lamp of the present exemplary embodiment, as shown inFIG. 1A, the base members 2 a and 2 b can be screwed to the front parts3 a 1 and 3 b 1 of the heat sinks 3 a and 3 b, respectively. Thepresently disclosed subject matter is not limited thereto, however.Instead, the base members and the front parts of the respective heatsinks may be joined by using a heat conductive joining member such as aheat conductive tape, adhesives, or other attachment structure.

In the vehicle lamp of the present exemplary embodiment, as shown inFIGS. 1A and 2A, a rear part 3 a 2 (upper part, in the diagrams) of thegenerally L-shaped heat sink 3 a and a rear part 3 b 2 (upper part, inthe diagrams) of the generally L-shaped heat sink 3 b can be screwed(see FIG. 2A) or otherwise joined to each other.

Put another way, the vehicle lamp according to the present exemplaryembodiment can include a plurality of light emitting devices 1 a and 1 band heat sinks 3 a and 3 b configured to dissipate heat generated by theplurality of light emitting devices 1 a and 1 b as shown in FIG. 1A. Thefront part 3 a 1 of the heat sink 3 a and the front part 3 b 1 of theheat sink 3 b can be branched so that the heat sinks 3 a and 3 b form agenerally Y-shaped configuration in a horizontal cross-section thatincludes the primary optical axis CL of the vehicle lamp.

Consequently, in the vehicle lamp of the present exemplary embodiment,as shown in FIG. 1A, the heat generated by the light emitting device 1 acan be dissipated by the front part 3 a 1 of the heat sink 3, not onlyfrom the side where the light emitting device 1 a is connected (the leftside, in the diagram; more specifically, the surface of the base member2 a) but also from the side where the light emitting device 1 a is notconnected (the right side, in the diagram).

The heat generated by the light emitting device 1 b can be dissipated bythe front part 3 b 1 of the heat sink 3, not only from the side wherethe light emitting device 1 b is connected (the right side, in thediagram; more specifically, the surface of the base member 2 b) but alsofrom the side where the light emitting device 1 b is not connected (theleft side, in the diagram).

According to the vehicle lamp of the present exemplary embodiment, it istherefore possible to improve the efficiency of heat dissipation withrespect to the heat generated by the plurality of light emitting devices1 a and 1 b when compared with the conventional vehicle lamp where theheat sink (radiator plate) is formed in a generally I-shapedconfiguration when seen in a vertical plane that includes the primaryoptical axis of the vehicle lamp. That is, the vehicle lamp of thepresent exemplary embodiment can dissipate the heat generated by theplurality of light emitting devices 1 a and 1 b by means of the heatsinks 3 a and 3 b.

The vehicle lamp of the present exemplary embodiment can thus avoid ashortened life, dropped luminous intensity, and discolored light of thelight emitting devices 1 a and 1 b, which might result from insufficientdissipation of the heat generated by the plurality of light emittingdevices 1 a and 1 b.

In the vehicle lamp of the present exemplary embodiment, as shown inFIGS. 1A and 2A, the rear part 3 a 2 (upper part, in the diagrams) ofthe generally L-shaped heat sink 3 a and the rear part 3 b 2 of thegenerally L-shaped heat sink 3 b can be screwed to each other (see FIG.2A). The presently disclosed subject matter is not limited thereto,however. Instead, the heat sinks may be joined to each other by using aheat conductive joining member such as a heat conductive tape or otherattachment or adhesive structures.

In the vehicle lamp of the present exemplary embodiment, as shown inFIG. 1A, the front part 3 a 1 of the heat sink 3 a and the front part 3b 1 of the heat sink 3 b can be branched so that the heat sinks 3 a and3 b have a generally Y-shaped configuration as viewed in the horizontalsection including the primary optical axis CL of the vehicle lamp. Thepresently disclosed subject matter is not limited thereto, however.Instead, the front part 3 a 1 of the heat sink 3 a and the front part 3b 1 of the heat sink 3 b may be branched so that the heat sinks have agenerally Y-shaped configuration in a vertical section that includes theprimary optical axis CL of the vehicle lamp, or in an arbitrary crosssection including the primary optical axis CL of the vehicle lamp otherthan the horizontal section or the vertical section.

In the vehicle lamp according to the present exemplary embodiment, asshown in FIG. 1A, the two generally L-shaped heat sinks 3 a and 3 b canbe joined into the generally Y-shaped assembly of the heat sinks 3 a and3 b. The presently disclosed subject matter is not limited thereto,however. Instead, a heat sink of generally Y-shaped configuration may bemade of a single member that is so formed by molding, such as aluminumdie-casting.

In the accompanying drawings, the reference numerals 3 a 2 a and 3 a 2 bdesignate areas where the rear part 3 a 2 of the heat sink 3 a and ahousing 6 are thermally connected with each other. The referencenumerals 3 b 2 a and 3 b 2 b designate areas where the rear part 3 b 2of the heat sink 3 b and the housing 6 are thermally connected with eachother. The reference numeral 4 a designates a heat sink that isinterposed between the rear part 3 a 2 of the heat sink 3 a and a leftpart 5 a of the flexible substrate 5. The reference numeral 4 bdesignates a heat sink that is interposed between the rear part 3 b 2 ofthe heat sink 3 b and a right part 5 b of the flexible substrate 5. Inthe vehicle lamp of the present exemplary embodiment, the heat sinks 4 aand 4 b can be made of a high heat conductive material such as aluminum.The housing 6 can be made of a high heat conductive and high thermaldissipation material such as die-cast aluminum.

In the accompanying drawings, the reference numeral 5 a 1 designates acoupler that is mounted on the left part 5 a of the flexible substrate 5for the sake of supplying power to the light emitting device 1 a. Thereference numeral 5 b 1 designates a coupler that is mounted on theright part 5 b of the flexible substrate 5 for the sake of supplyingpower to the light emitting device 1 b. The reference numeral 5 b 2designates a coupler that is mounted on the right part 5 b of theflexible substrate 5 for the sake of connecting the flexible substrate 5with an external power supply (not shown).

In the accompanying drawings, the reference numeral 8 designates anouter lens. The reference numeral 8 a designates a plain lens area whichconstitutes a part of the outer lens 8. The reference numeral 8 bdesignates a lens cut area which constitutes a part of the outer lens 8.

In the vehicle lamp according to the present exemplary embodiment, astypically shown in FIGS. 1B, 3A, and 3B, the reflector 7 can have areflector part 7 a configured to reflect the light emitted from thelight emitting device 1 a toward the front of the vehicle lamp(downward, in FIGS. 3A and 3B). As typically shown in FIGS. 1B, 4A, and4B, the reflector 7 can also have a reflector part 7 b configured toreflect the light emitted from the light emitting device 1 b toward thefront of the vehicle lamp (downward, in FIGS. 4A and 4B).

The reflector part 7 a can have the reflecting surface 7 a 1 configuredto reflect light beams that are emitted from the light emitting device 1a behind (above, in FIG. 3A) the primary optical axis CL1 a of the lightemitting device 1 a with respect to the direction of the vehicle lamp.The reflector part 7 a can also have the reflecting surface 7 a 2configured to reflect light beams that are emitted from the lightemitting device 1 a in a frontward direction (below, in FIG. 3B) of theprimary optical axis CL1 a of the light emitting device 1 a with respectto the direction of the vehicle lamp.

Furthermore, the reflector part 7 b can have the reflecting surface 7 b1 configured to reflect light beams that are emitted from the lightemitting device 1 b behind (above, in FIG. 4A) the primary optical axisCL1 b of the light emitting device 1 b with respect to the direction ofthe vehicle lamp. The reflector part 7 b can also have the reflectingsurface 7 b 2 configured to reflect light beams that are emitted fromthe light emitting device 1 b in a frontward direction (below, in FIG.4B) of the primary optical axis CL1 b of the light emitting device 1 bwith respect to the direction of the vehicle lamp.

More specifically, in the vehicle lamp of the present exemplaryembodiment, as shown in FIG. 3A, the light beams L1 and L2 reflectedfrom the reflecting surface 7 a 1 can be projected forward (downward, inthe diagram) of the vehicle lamp at relatively small angles, forexample, at around 10° to the primary optical axis CL of the vehiclelamp (and an axis CL′ parallel thereto). As shown in FIG. 3B, the lightbeam L3 reflected from the reflecting surface 7 a 2 can be projected tothe front right (bottom right, in the diagram) of the vehicle lamp atrelatively small angles, for example, at around 5° to the primaryoptical axis CL of the vehicle lamp. As shown in FIG. 3B, the light beamL4 reflected from the reflecting surface 7 a 2 can be refracted throughthe lens cuts 8 b of the outer lens 8, and projected to the front right(lower right, in the diagram) of the vehicle lamp at relatively largeangles, for example, at around 50° to the primary optical axis CL of thevehicle lamp. As shown in FIG. 3B, the light beam L5 reflected from thereflecting surface 7 a 2 can be refracted through the lens cuts 8 b ofthe outer lens 8, and projected to the front right (lower right, in thediagram) of the vehicle lamp at relatively large angles, for example, ataround 80° to the primary optical axis CL of the vehicle lamp. That is,the light beams L1 and L2 reflected from the reflecting surface 7 a 1can be more condensed and brighter than the light beams L3, L4, and L5reflected from the reflecting surface 7 a 2. In this exemplaryembodiment, around 10° are exemplified as relatively small angles. Inaccordance with the presently disclosed subject matter, when therelatively small angles of approximately 20° or smaller can providecondensed beams of light, thereby reducing the size of the Y-shaped heatsink in the thickness direction.

Furthermore, in the vehicle lamp of the present exemplary embodiment, asshown in FIG. 4A, the light beams L6 and L7 reflected from thereflecting surface 7 b 1 can be projected forward (downward, in thediagram) of the vehicle lamp at relatively small angles, for example, ataround 10° to the primary optical axis CL of the vehicle lamp (and theaxis CL′ parallel thereto). As shown in FIG. 4B, the light beam L8reflected from the reflecting surface 7 b 2 can be projected to thefront left (bottom left, in the diagram) of the vehicle lamp atrelatively small angles, for example, at around 5° to the primaryoptical axis CL of the vehicle lamp. As shown in FIG. 4B, the light beamL9 reflected from the reflecting surface 7 b 2 can be refracted throughthe lens cuts 8 b of the outer lens 8, and projected to the front left(lower left, in the diagram) of the vehicle lamp at relatively largeangles, for example, at around 50° to the primary optical axis CL of thevehicle lamp. As shown in FIG. 4B, the light beam L10 reflected from thereflecting surface 7 b 2 can be refracted through the lens cuts 8 b ofthe outer lens 8, and projected to the front left (lower left, in thediagram) of the vehicle lamp at relatively large angles, for example, ataround 80° to the primary optical axis CL of the vehicle lamp. That is,the light beams L6 and L7 reflected from the reflecting surface 7 b 1can be more condensed and brighter than the light beams L8, L9, and L10that are reflected from the reflecting surface 7 b 2.

In the vehicle lamp of the present exemplary embodiment, as shown inFIG. 3B, the light beams L4 and L5 that are emitted from the lightemitting device 1 a in a frontward direction (below, in the diagram) ofthe vehicle lamp are reflected from the reflecting surface 7 a 2 of thereflector part 7 a so as to be projected in front of the vehicle lamp atrelatively large angles with respect to the primary optical axis CL ofthe vehicle lamp.

Consequently, according to the vehicle lamp of the present exemplaryembodiment, as shown in FIG. 3B, the reflector part 7 a can be reducedin size when compared with the case where the light beams L4 and L5 thatare emitted from the light emitting device 1 a in the frontwarddirection (below, in the diagram) of the vehicle lamp and are reflectedfrom the reflecting surface 7 a 2 of the reflector part 7 a so as to beprojected in front of the vehicle lamp at relatively small angles withrespect to the primary optical axis CL of the vehicle lamp.

In the vehicle lamp of the present exemplary embodiment, as shown inFIG. 4B, the light beams L9 and L10 that are emitted from the lightemitting device 1 b in the frontward direction (below, in the diagram)of the vehicle lamp are reflected from the reflecting surface 7 b 2 ofthe reflector part 7 b so as to be projected in front of the vehiclelamp at relatively large angles with respect to the primary optical axisCL of the vehicle lamp.

Consequently, according to the vehicle lamp of the present exemplaryembodiment, as shown in FIG. 4B, the reflector part 7 b can be reducedin size when compared with the case where the light beams L9 and L10that are emitted from the light emitting device 1 b in the frontwarddirection (below, in the diagram) of the vehicle lamp are reflected fromthe reflecting surface 7 b 2′ of the reflector part 7 b so as to beprojected in front of the vehicle lamp at relatively small angles withrespect to the primary optical axis CL of the vehicle lamp.

As shown in FIGS. 3B and 4B, the vehicle lamp of the present exemplaryembodiment can also be configured so that the light beams L4 and L5reflected from the reflecting surface 7 a 2 and the light beams L9 andL10 reflected from the reflecting surface 7 b 2 cross each other nearthe primary optical axis CL of the vehicle lamp. The outer lens 8 canhave a lens cut area 8 b near the position where the light beams L4 andL5 reflected from the reflecting surface 7 a 2 and the light beams L9and L10 reflected from the reflecting surface 7 b 2 cross each other.

More specifically, the lens cut area 8 b formed on the outer lens 8 candiffuse the light beams L4 and L5 reflected from the reflecting surface7 a 2. The lens cut area 8 b can also diffuse the light beams L9 and L10reflected from the reflecting surface 7 b 2.

According to the vehicle lamp of the present exemplary embodiment, theouter lens 8 can be reduced in size when compared with the case where alens cut area 8 b configured to diffuse the light beams L4 and L5reflected from the reflecting surface 7 a 2 and a lens cut area 8 bconfigured to diffuse the light beams L9 and L10 reflected from thereflecting surface 7 b 2 are provided separately from the outer lens 8.This also allows the miniaturization of the entire vehicle lamp.

In the vehicle lamp of the present exemplary embodiment, as shown inFIG. 1A, the lens cut area 8 b can be arranged in front (under, in thediagram) of the heat sinks 3 a and 3 b, or more specifically, in frontof the branched front parts 3 a 1 and 3 b 1 of the heat sinks 3 a and 3b. As shown in FIG. 1B, the outlines 3 a 1′ and 3 b 1′ of the branchedfront parts 3 a 1 and 3 b 1 of the heat sinks 3 a and 3 b and theoutline 8 b′ of the lens cut area 8 b can be generally consistent witheach other when seen from the front of the vehicle lamp. The outlinescan be defined by an outer periphery of each of the devices as viewedfrom a front of the lamp along the optical axis.

According to the vehicle lamp of the present exemplary embodiment, thelens cut area 8 b can thus prevent the heat sinks 3 a and 3 b, or thebranched front part 3 a 1 of the heat sink 3 a and the branched frontpart 3 b 1 of the heat sink 3 b in particular, from being visible fromthe front of the vehicle lamp.

That is, the lens cut area 8 b configured to diffuse the light beams L4and L5 reflected from the reflecting surface 7 a 2 and the light beamsL9 and L10 reflected from the reflected surface 7 b 2 can be used as ameans for preventing the heat sinks 3 a and 3 b, or the branched frontpart 3 a 1 of the heat sink 3 a and the branched front part 3 b 1 of theheat sink 3 b, from being visible from the front of the vehicle lamp.

Thus, it is possible to suppress the cost of the entire vehicle lampwhen compared with the case where a means for preventing the heat sinks3 a and 3 b, or the branched front parts 3 a 1 and 3 b 1 of the heatsinks 3 a and 3 b, from being visible from the front of the vehicle lampis provided separately from the lens cut area 8 b configured to diffusethe light beams L4 and L5 reflected from the reflecting surface 7 a 2and the light beams L9 and L10 reflected from the reflected surface 7 b2.

As shown in FIG. 1A, the flexible substrate 5 configured to supply powerto the light emitting devices 1 a and 1 b can be connected with the leftside (left side, in the diagram) and right side (right side, in thediagram) of the unbranched rear parts 3 a 2 and 3 b 2 of the heat sinks3 a and 3 b, respectively.

In the vehicle lamp of the present exemplary embodiment, as shown inFIGS. 1A and 2A, the unbranched rear part 3 a 2 of the heat sink 3 a canbe put into contact and thermally connected with the housing 6 at theend area 3 a 2 a (top end, in the diagrams) opposite from the branchedfront part 3 a 1 of the heat sink 3 a. An area 3 a 2 b lying on theborder between the branched front part 3 a 1 of the heat sink 3 a andthe unbranched rear part 3 a 2 of the heat sink 3 a can also be put intocontact and thermally connected with the housing 6.

More specifically, the left part 5 a of the flexible substrate 5 can beconnected with the left side (left side, in the diagrams) of theunbranched rear part 3 a 2 of the heat sink 3 a. Some of the heatgenerated by components on this left part 5 a can then be transferred tothe housing 6 through the rear end area 3 a 2 a (top end, in thediagrams) of the rear part 3 a 2 of the heat sink 3 a, and dissipatedfrom the housing 6.

In the vehicle lamp of the present exemplary embodiment, as shown inFIGS. 1A and 2A, some of the heat generated by the components on theleft part 5 a of the flexible substrate 5, in connection with the leftside (left side, in the diagrams) of the unbranched rear part 3 a 2 ofthe heat sink 3 a, can also be transferred to the housing 6 through thearea 3 a 2 b lying on the border between the front part 3 a 1 and therear part 3 a 2 of the heat sink 3 a, and dissipated from the housing 6.

That is, the heat generated by the components on the left part 5 a ofthe flexible substrate 5 in connection with the left side (left side, inthe diagram) of the unbranched rear part 3 a 2 of the heat sink 3 a isprevented from being transferred to the front part 3 a 1 of the heatsink 3 a where the light emitting device 1 a is connected.

The vehicle lamp of the present exemplary embodiment can thus prevent adrop in the efficiency of heat dissipation for the light emitting device1 a, which might result if the heat generated by the components on theleft part 5 a of the flexible substrate 5 is transferred to the branchedfront part 3 a 1 of the heat sink 3 a where the light emitting device 1a is connected.

In other words, in the vehicle lamp of the present exemplary embodiment,heat dissipation channels can be provided for the heat that is generatedby the components on the left part 5 a of the flexible substrate 5.Thus, the heat generated by the components on the left part 5 a of theflexible substrate 5 is dissipated without reaching the light emittingdevice 1 a.

The vehicle lamp of the present exemplary embodiment can thus improvethe efficiency of heat radiation for the light emitting device 1 a whencompared with the case where sufficient heat dissipation channels arenot provided for the heat that is generated by the components on theleft part 5 a of the flexible substrate 5.

Furthermore, in the vehicle lamp of the present exemplary embodiment, asshown in FIGS. 1A and 2A, the unbranched rear part 3 b 2 of the heatsink 3 b can be put into contact and thermally connected with thehousing 6 at the end area 3 b 2 a (top end, in the diagrams) oppositefrom the branched front part 3 b 1 of the heat sink 3 b. An area 3 b 2 blying on the border between the branched front part 3 b 1 of the heatsink 3 b and the unbranched rear part 3 b 2 of the heat sink 3 b canalso be put into contact and thermally connected with the housing 6.

More specifically, the right part 5 b of the flexible substrate 5 can beconnected with the right side (right side, in the diagrams) of theunbranched rear part 3 b 2 of the heat sink 3 b. Some of the heatgenerated by components on this right part 5 b can then be transferredto the housing 6 through the rear end area 3 b 2 a (top end, in thediagrams) of the rear part 3 b 2 of the heat sink 3 b, and dissipatedfrom the housing 6.

In the vehicle lamp of the present exemplary embodiment, as shown inFIGS. 1A and 2A, some of the heat generated by the components on theright part 5 b of the flexible substrate 5, in connection with the rightside (right side, in the diagrams) of the unbranched rear part 3 b 2 ofthe heat sink 3 b, can also be transferred to the housing 6 through thearea 3 b 2 b lying on the border between the front part 3 b 1 and therear part 3 b 2 of the heat sink 3 b, and dissipated from the housing 6.

That is, the heat generated by the components on the right part 5 b ofthe flexible substrate 5 in connection with the right side (right side,in the diagram) of the unbranched rear part 3 b 2 of the heat sink 3 bcan be prevented from being transferred to the front part 3 b 1 of theheat sink 3 b where the light emitting device 1 a is connected.

The vehicle lamp of the present exemplary embodiment can thus prevent adrop in the efficiency of heat dissipation for the light emitting device1 a, which might result if the heat generated by the components on theright part 5 b of the flexible substrate 5 is transferred to thebranched front part 3 b 1 of the heat sink 3 b where the light emittingdevice 1 b is connected.

In other words, in the vehicle lamp of the present exemplary embodiment,heat dissipation channels can be provided for the heat that is generatedby the components on the right part 5 b of the flexible substrate 5 sothat the heat generated by the components on the right part 5 b of theflexible substrate 5 is dissipated without reaching the light emittingdevice 1 b.

The vehicle lamp of the present exemplary embodiment can thus improvethe efficiency of heat radiation for the light emitting device 1 b whencompared with the case where sufficient heat dissipation channels arenot provided for the heat that is generated by the components on theright part 5 b of the flexible substrate 5 that is configured to supplypower to the light emitting device 1 b.

In the vehicle lamp of the present exemplary embodiment, as shown inFIG. 1A, the heat sink 4 a can be interposed between the rear part 3 a 2of the heat sink 3 a and the left part 5 a of the flexible substrate 5.The heat sink 4 b can be interposed between the rear part 3 b 2 of theheat sink 3 b and the right part 5 b of the flexible substrate 5. Thepresently disclosed subject matter is not limited thereto, however.Instead, the heat sink between the rear part of the heat sink and theleft part (right part) of the flexible substrate may be omitted.

In the vehicle lamp of the present exemplary embodiment, as shown inFIGS. 1A, 2B, and 2C, the circuit substrate configured to supply powerto the light emitting devices 1 a and 1 b can be made of the flexiblesubstrate 5. The left part 5 a of the flexible substrate 5 can beconnected with the left side (left side in FIG. 1A) of the unbranchedrear part 3 a 2 of the heat sink 3 a. The right part 5 b of the flexiblesubstrate 5 can be connected with the right side (right side in FIG. 1A)of the unbranched rear part 3 b 2 of the heat sink 3 b.

According to the vehicle lamp of the present exemplary embodiment, it istherefore possible to reduce the parts count of the entire vehicle lamp,and by extension the assembly cost of the entire vehicle lamp, whencompared with the case where a rigid substrate is connected to the leftside of the unbranched rear part 3 a 2 of the heat sink 3 a, and anotherrigid substrate is connected to the right side of the unbranched rearpart 3 b 2 of the heat sink 3 b. More specifically, according to thevehicle lamp of the present exemplary embodiment, it is possible toreduce the number of substrates, as well as wiring, couplers, and thelike for connecting one rigid substrate to the other rigid substrate.This allows the miniaturization of the entire vehicle lamp.

The vehicle lamp of the present exemplary embodiment can also improvethe packaging density of the components on the circuit substrate whencompared with the case where a rigid substrate is connected to the leftside (left side, in FIG. 1A) of the unbranched rear part 3 a 2 of theheat sink 3 a, and another rigid substrate is connected to the rightside (right side, in FIG. 1A) of the unbranched rear part 3 b 2 of theheat sink 3 b. More specifically, using the thin flexible substrate 5with low thermal resistance, the vehicle lamp of the present exemplaryembodiment can transfer the heat generated by the components on theflexible substrate 5 to the heat sinks 3 a and 3 b quickly. This canreduce the thermal load on the components, so that a plurality ofcomponents can be mounted on the flexible substrate 5 with an increasedpackage density.

In the vehicle lamp of the present exemplary embodiment, the heat sink 4a can be joined to the left part 5 a of the flexible substrate 5 inadvance as shown in FIG. 2C before the left part 5 a of the flexilesubstrate 5 is connected with the left side of the unbranched rear part3 a 2 of the heat sink 3 a as shown in FIG. 1A.

Furthermore, the heat sink 4 b can be joined to the right part 5 b ofthe flexible substrate 5 in advance as shown in FIG. 2C before the rightpart 5 b of the flexile substrate 5 is connected with the right side ofthe unbranched rear part 3 b 2 of the heat sink 3 b.

The heat sink 4 a can also be joined to the left side of the unbranchedrear part 3 a 2 of the heat sink 3 a, whereby the left part 5 a of theflexible substrate 5 is connected with the left side of the rear part 3a 2 of the heat sink 3 a.

Furthermore, the heat sink 4 b can also be joined to the right side(right side in the drawing) of the unbranched rear part 3 b 2 of theheat sink 3 b, whereby the right part 5 b of the flexible substrate 5 isconnected with the right side of the rear part 3 b 2 of the heat sink 3b.

The vehicle lamp of the presently disclosed subject matter therebyallows improved workability when assembling the flexible substrate 5 andthe heat sinks 3 a and 3 b when compared with the case where the leftpart 5 a of the flexible substrate 5 is directly joined to the left sideof the rear part 3 a 2 of the heat sink 3 a, and the right part 5 b ofthe flexible substrate 5 is directly jointed to the right side of therear part 3 b 2 of the heat sink 3 b.

In the vehicle lamp of the present exemplary embodiment, the left sideof the rear part 3 a 2 of the heat sink 3 a and the heat sink 4 a can bejoined by a heat conductive joining member such as a heat conductivetape or other known connection structure. The heat sink 4 a and the leftpart 5 a of the flexible substrate 5 can be joined by a heat conductivejoining member such as a heat conductive tape or other known connectionstructure. The right side of the rear part 3 b 2 of the heat sink 3 band the heat sink 4 b can be joined by a heat conductive joining membersuch as a heat conductive tape or other known connection structure. Theheat sink 4 b and the right part 5 b of the flexible substrate 5 can bejoined by a heat conductive joining member such as a heat conductivetape or other known connection structure. The presently disclosedsubject matter is not limited thereto, however. Instead, these portionsmay be joined by arbitrary other joining methods and structures.

The foregoing embodiments of the presently disclosed subject matter andmodifications thereof may be combined as appropriate.

The vehicle lamp according to the presently disclosed subject matter maybe applied, for example, to a headlamp, turn signal lamp, position lamp,daytime running lamp, high beam lamp, fog lamp, tail lamp, stop lamp,traffic lamp, spot lamp, etc.

It will be apparent to those skilled in the art that variousmodifications and variations can be made in the presently disclosedsubject matter without departing from the spirit or scope of theinvention. Thus, it is intended that the presently disclosed subjectmatter cover the modifications and variations of the presently disclosedsubject matter provided they come within the scope of the appendedclaims and their equivalents. All related art references described aboveare hereby incorporated in their entirety by reference.

1. A lamp configured to emit light in a frontward light emittingdirection along a primary optical axis of the lamp, comprising: aplurality of light emitting devices including at least a first lightemitting device and a second light emitting device; and a first heatsink configured to dissipate heat generated by the plurality of lightemitting devices, the first heat sink having a first branched part and asecond branched part forming a generally Y-shaped configuration asviewed in a section that includes the primary optical axis of the lamp,the first branched part being connected with at least the first lightemitting device, the second branched part being connected with at leastthe second light emitting device.
 2. The lamp according to claim 1,further comprising: a first reflector configured to reflect lightemitted from the first light emitting device toward the frontwarddirection with respect to the primary optical axis of the lamp, thefirst reflector having a first reflecting surface configured to reflecta beam of light that is emitted from the first light emitting device ina direction that is rearward with respect to the primary optical axis ofthe lamp, and a second reflecting surface configured to reflect a beamof light that is emitted from the first light emitting device in thefrontward direction with respect to the primary optical axis of thelamp; and a second reflector configured to reflect light emitted fromthe second light emitting device toward the frontward direction withrespect to the primary optical axis of the lamp, the second reflectorhaving a third reflecting surface configured to reflect a beam of lightthat is emitted from the second light emitting device in a directionthat is rearward with respect to the primary optical axis of the lamp,and a fourth reflecting surface configured to reflect a beam of lightthat is emitted from the second light emitting device in the frontwarddirection with respect to the primary optical axis of the lamp, andwherein the beam of light reflected from the first reflecting surfaceand the beam of light reflected from the third reflecting surface areprojected frontward with respect to the primary optical axis of the lampand each at a relatively small angle with respect to the primary opticalaxis of the lamp, and wherein the beam of light reflected from thesecond reflecting surface and the beam of light reflected from thefourth reflecting surface are projected frontward with respect to theprimary optical axis of the lamp and each at a relatively larger anglewith respect to the primary optical axis of the lamp as compared to eachrelatively small angle.
 3. The lamp according to claim 2, furthercomprising: an outer lens, and wherein the first and second reflectorare configured such that the beam of light reflected from the secondreflecting surface and the beam of light reflected from the fourthreflecting surface cross each other substantially at the primary opticalaxis of the lamp, and wherein the outer lens has a lens cut areasubstantially at a position where the beam of light reflected from thesecond reflecting surface and the beam of light reflected from thefourth reflecting surface cross each other.
 4. The lamp according toclaim 3, wherein the lens cut area is arranged in front of the first andsecond branched parts of the first heat sink, and wherein outerperimeters of the first and second branched parts and an outer perimeterof the lens cut area are generally consistent with and substantiallyoverlap each other when viewed from the front with respect to theprimary optical axis of the lamp.
 5. The lamp according to claim 1,further comprising: a circuit substrate configured to supply power tothe plurality of light emitting devices, the circuit substrate connectedwith the first heat sink at first and second sides of an unbranched partof the first heat sink, wherein an end of the unbranched part oppositefrom the first and second branched parts is thermally connected with ahousing of the lamp, and a border area between the first and secondbranched parts and the unbranched part is thermally connected with thehousing of the lamp.
 6. The lamp according to claim 2, furthercomprising: a circuit substrate configured to supply power to theplurality of light emitting devices connected with the first heat sinkat first and second sides of an unbranched part of the first heat sink,wherein an end of the unbranched part opposite from the first and secondbranched parts is thermally connected with a housing of the lamp, and aborder area between the first and second branched parts and theunbranched part is thermally connected with the housing of the lamp. 7.The lamp according to claim 3, further comprising: a circuit substrateconfigured to supply power to the plurality of light emitting devicesconnected with the first heat sink at first and second sides of anunbranched part of the first heat sink, wherein an end of the unbranchedpart opposite from the first and second branched parts is thermallyconnected with a housing of the lamp, and a border area between thefirst and second branched parts and the unbranched part is thermallyconnected with the housing of the lamp.
 8. The lamp according to claim4, further comprising: a circuit substrate configured to supply power tothe plurality of light emitting devices, the circuit substrate beingconnected with the first heat sink at first and second sides of anunbranched part of the first heat sink, wherein an end of the unbranchedpart opposite from the first and second branched parts is thermallyconnected with a housing of the lamp, and a border area between thefirst and second branched parts and the unbranched part is thermallyconnected with the housing of the lamp.
 9. The lamp according to claim5, wherein the circuit substrate configured to supply power to theplurality of light emitting devices is made of a flexible substrate, ahalf of the flexible substrate being connected with the first side ofthe unbranched part of the first heat sink, and an other half of theflexible substrate being connected with the second side of theunbranched part of the first heat sink.
 10. The lamp according to claim6, wherein the circuit substrate configured to supply power to theplurality of light emitting devices is made of a flexible substrate, ahalf of the flexible substrate being connected with the first side ofthe unbranched part of the first heat sink, and an other half of theflexible substrate being connected with the second side of theunbranched part of the first heat sink.
 11. The lamp according to claim7, wherein the circuit substrate configured to supply power to theplurality of light emitting devices is made of a flexible substrate, ahalf of the flexible substrate being connected with the first side ofthe unbranched part of the first heat sink, and an other half of theflexible substrate being connected with the second side of theunbranched part of the first heat sink.
 12. The lamp according to claim8, wherein the circuit substrate configured to supply power to theplurality of light emitting devices is made of a flexible substrate, ahalf of the flexible substrate being connected with the first side ofthe unbranched part of the first heat sink, and an other half of theflexible substrate being connected with the second side of theunbranched part of the first heat sink.
 13. A method for manufacturingthe lamp according to claim 9, the method comprising: joining a secondheat sink to the half of the flexible substrate in advance and beforethe half of the flexible substrate is connected with the first side ofthe unbranched part of the first heat sink; joining a third heat sink tothe other half of the flexible substrate in advance and before the otherhalf of the flexible substrate is connected with the second side of theunbranched part of the first heat sink; joining the second heat sink tothe first side of the unbranched part of the first heat sink, therebyconnecting the half of the flexible substrate with the first side of theunbranched part of the first heat sink; and joining the third heat sinkto the second side of the unbranched part of the first heat sink,thereby connecting the other half of the flexible substrate with thesecond side of the unbranched part of the first heat sink.
 14. The lampaccording to claim 1, wherein the lamp is configured as a vehicle lamp.15. A lamp configured to emit light in a light emitting direction alonga primary optical axis of the lamp, comprising: a plurality of lightemitting devices including at least a first light emitting device and asecond light emitting device; and a first heat sink configured todissipate heat generated by the plurality of light emitting devices, thefirst heat sink having, a first rear body part, a first branched partextending from the first rear body part and including a first partinterior surface, and a second branched part extending from the firstrear body part and including a second part interior surface separatefrom and facing the first part interior surface, wherein the firstbranched part of the heat sink is connected with at least the firstlight emitting device, and the second branched part is connected with atleast the second light emitting device.
 16. The lamp according to claim15, wherein the heat sink is comprised of aluminum.
 17. The lampaccording to claim 15, wherein the first branched part includes anexterior surface directly opposed to the first part interior surface,and the second branched part includes an exterior surface directlyopposed to the second part interior surface, and the first lightemitting device is connected to the first branched part exterior surfaceand the second light emitting device is connected to the second branchedpart exterior surface.
 18. The lamp according to claim 15, furthercomprising: a first reflector configured to reflect light emitted fromthe first light emitting device into the light emitting direction, thefirst reflector having a first reflecting surface configured to reflecta beam of light that is emitted from the first light emitting device ina rearward direction that is defined by adding a vector of directionextending in a rearward direction parallel with the primary optical axisof the lamp to a sideward vector of direction extending in a sidewarddirection perpendicular to the primary optical axis, and the firstreflector having a second reflecting surface configured to reflect abeam of light that is emitted from the first light emitting device in afrontward direction that is defined by adding a vector of directionextending in a frontward direction parallel with the primary opticalaxis of the lamp to a sideward vector of direction extending in asideward direction perpendicular to the primary optical axis; and asecond reflector configured to reflect light emitted from the secondlight emitting device into the light emitting direction, the secondreflector having a third reflecting surface configured to reflect a beamof light that is emitted from the second light emitting device in arearward direction that is defined by adding a vector of directionextending in a rearward direction parallel with the primary optical axisof the lamp to a sideward vector of direction extending in a sidewarddirection perpendicular to the primary optical axis, and the secondreflector having a fourth reflecting surface configured to reflect abeam of light that is emitted from the second light emitting device in afrontward direction that is defined by adding a vector of directionextending in a frontward direction parallel with the primary opticalaxis of the lamp to a sideward vector of direction extending in asideward direction perpendicular to the primary optical axis, whereinthe first and second reflectors are configured such that the beam oflight reflected from the first reflecting surface and the beam of lightreflected from the third reflecting surface are projected in thefrontward direction each at a relatively small angle with respect to theprimary optical axis of the lamp, and the first and second reflectorsare configured such that the beam of light reflected from the secondreflecting surface and the beam of light reflected from the fourthreflecting surface are projected in the frontward direction and atrelatively larger angles with respect to the primary optical axis of thelamp as compared to each small angle.
 19. The lamp according to claim18, further comprising: an outer lens, wherein the first and secondreflectors are configured such that the beam of light reflected from thesecond reflecting surface and the beam of light reflected from thefourth reflecting surface cross each other substantially at the primaryoptical axis of the lamp, and the outer lens has a lens cut areasubstantially at a position where the beam of light reflected from thesecond reflecting surface and the beam of light reflected from thefourth reflecting surface cross each other.
 20. The lamp according toclaim 15, further comprising: a circuit substrate configured to supplypower to the plurality of light emitting devices connected with thefirst heat sink at first and second sides of the rear body part of thefirst heat sink, wherein an end of the rear body part opposite from thefirst and second branched parts is thermally connected with a housing ofthe lamp, and a border area between the first and second branched partsand the rear body part is thermally connected with the housing of thelamp.